PATTERNS IN DECOMPOSITION RATES AMONG PHOTOSYNTHETIC ORGANISMS - THE IMPORTANCE OF DETRITUS C-N-P CONTENT

The strength and generality of the relationship between decomposition rates and detritus carbon, nitrogen, and phosphorus concentrations was assessed by comparing published reports of decomposition rates of det ritus of photosynthetic organisms, from unicellular algae to trees. Th e results obtained demonstrated the existence of a general positive, l inear relationship between plant decomposition rates and nitrogen and phosphorus concentrations. Differences in the carbon, nitrogen, and ph osphorus concentrations of plant detritus accounted for 89% of the var iance in plant decomposition rates of detritus originating from photos ynthetic organisms ranging from unicellular microalgae to trees. The r esults also demonstrate that moist plant material decomposes substanti ally faster than dry material with similar nutrient concentrations. Co nsideration of lignin, instead of carbon, concentrations did not impro ve the relationships obtained. These results reflect the coupling of p hosphorus and nitrogen in the basic biochemical processes of both plan ts and their microbial decomposers, and stress the importance of this coupling for carbon and nutrient flow in ecosystems.